What it means
The CU raises this alarm when, after the drive system is switched on, the synchronization between the basic clock cycle, the DRIVE-CLiQ clock cycle and the application clock cycle was started but was not completed within the selected time tolerance. The alarm itself triggers no automatic reaction and does not need to be acknowledged.
Why it appears
- After the drive system was switched on, the synchronization between the basic clock cycle, the DRIVE-CLiQ clock cycle and the application clock cycle started but was not completed within the selected time tolerance.
What to check
- Carry out a POWER ON for all components of the DO: switch each component off and then switch it back on.
Reading the message value
- The drive stores an alarm value in r2124, which is interpreted as a decimal number. The manual prints no decoding for this alarm: the value is only for internal Siemens troubleshooting.
Parameters the manual names
- r2124 — alarm value of this alarm, read as a decimal number; for A01955 the manual states the content is only for internal Siemens troubleshooting, so it gives no indication you can act on yourself.
Acknowledging and restarting
No acknowledgement is required for this alarm. The only remedy the manual gives is: Carry out a POWER ON (switch-off/switch-on) for all components of the DO.
The same on every family
Every manual that describes A01955 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| G130, G150 | NONE | NONE | Internal (DRIVE-CLiQ) communication error (12) | None | SINAMICS G130, G150 List Manual · p. 1497 |
| S120, S150 | NONE | NONE | Internal (DRIVE-CLiQ) communication error (12) | None | SINAMICS S120, S150 List Manual · p. 2721 |
The drives this code lives on
A01955 is described for G130, G150, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does SINAMICS alarm A01955 mean?
It reports that after the drive system is switched on, the synchronization between the basic clock cycle, the DRIVE-CLiQ clock cycle and the application clock cycle was started but was not completed within the selected time tolerance.
How do I clear alarm A01955?
Carry out a POWER ON for all components of the DO, i.e. switch the components off and switch them back on. No acknowledgement of the alarm is required.
Does A01955 stop or trip the drive?
No automatic reaction is triggered by this alarm; it only reports the incomplete clock-cycle synchronization and does not need to be acknowledged.
What is the alarm value r2124 for A01955?
The drive writes an alarm value into r2124, which is interpreted as a decimal number. The manual states that this value is only for internal Siemens troubleshooting, so no decoding is given.
Codes next to this one
Source
Written from Siemens' own List Manuals and operating instructions; every number, designation and parameter on this page is checked against them before publication.
All SINAMICS codes: fault and alarm codes · the A01xxx group · SINAMICS manuals · Siemens manuals